By R. T. Daly and M. G. Cohen

This paper studies the technical feasibility of using
a free space cascade of optical (laser) links for CATV service.
By employing available Weather Bureau visibility statistics for
New York City, the effects of optical path attenuation on link reliability
are determined. Based upon these results, a link is proposed
which will provide 99.9% reliability with a 42 db signal-to-noise
ratio for transmission of 25 TV channels plus the FM band. Repeater
spacings, required optical powers, detailed configurations,
modulation techniques and costs are discussed.